This process is commonly used for the production of plastic sheets. During the extrusion of these plastic materials, the pulling technique is used for cooling. This cooling process is done through a specific set of cooling rolls that are generally three or four in number. These cooling rolls are also called “calendar” or “chill” rolls.

If this technique is done in extremely fast running speed, it develops a “nerve” which is an undesirable condition. This condition occurs when insufficient contact time is permitted to dissipate the heat in the extruded plastic.

In the plastic sheet extrusion, the rolls deliver the required cooling and determine the sheet thickness along with surface texture. This is done especially in the case of structured rolls i.e. levant, smooth, and haircalf.

Commonly, co-extrusion is used for applying one or more layer for a specific property like soft touch, grip, UV-absorption, matte surface or energy reflection.

The unit for the solid sheet extrusion comprises of minimum one extruder along with one sheet extrusion die. It is supported by a polishing stack which commonly includes 3 calendars that calibrate and cool the sheet with the use of their calendar nips or surfaces. Behind this, the draw-off rolls to cool air and the roller conveyor are located. Then, finally the sheet is cut and stored.